Direct Comparison of Measuring Labeling Yieldof Ga-68 Labeled Peptides Using HPLC and TLC Methods

1170 Objectives To assess the accuracy of measuring labeling yield of 68Ga labeled peptides using HPLC and TLC methods under the same conditions. Methods NOTA-NGR2 peptides were labeled with 68Ga under three different conditions: pH 0-1, 90℃, 15 min; pH 2.5-3.5, 42℃, 10 min; pH 2.5-3.5, 42℃, 5 min, each labeling condition was repeated 10 times. Labeling yield of each final product was measured using HPLC and TLC methods, respectively. In addition, the measured labeling yield was compared to the calculated labeling yield through C18 cartridge purified. The compairions of the labeling yield measured by HPLC, TLC methods and C18 cartridge purified were analyzed using SPSS16.0 software. Results The labeling yield measured by HPLC method was higher than the other two when the actual labeling yield was lower than 50% (p Conclusions The results revealed that TLC method was the more suitable method for measuring labeling yield of 68Ga labeled peptides compared to HPLC method.